Policastro Debora, Giorno Eugenia, Scarpelli Francesca, Godbert Nicolas, Ricciardi Loredana, Crispini Alessandra, Candreva Angela, Marchetti Fabio, Xhafa Sonila, De Rose Renata, Nucera Antonello, Barberi Riccardo C, Castriota Marco, De Bartolo Loredana, Aiello Iolinda
MAT-INLAB (Laboratorio di Materiali Molecolari Inorganici) and LASCAMM - CR INSTM, Unità INSTM of Calabria, Department of Chemistry and Chemical Technologies, University of Calabria Ponte Bucci, Rende, Italy.
CNR NANOTEC- Institute of Nanotechnology U.O.S. Cosenza, Rende, Italy.
Front Chem. 2022 May 31;10:884059. doi: 10.3389/fchem.2022.884059. eCollection 2022.
The improvement of the antioxidant and antimicrobial activities of chitosan (CS) films can be realized by incorporating transition metal complexes as active components. In this context, bioactive films were prepared by embedding a newly synthesized acylpyrazolonate Zn(II) complex, [Zn(Q)(MeOH)], into the eco-friendly biopolymer CS matrix. Homogeneous, amorphous, flexible, and transparent CS@Zn films were obtained through the solvent casting method in dilute acidic solution, using different weight ratios of the Zn(II) complex to CS and characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR), Raman, and scanning electron microscopy (SEM) techniques. The X-ray single-crystal analysis of [Zn(Q)(MeOH)] and the evaluation of its intermolecular interactions with a protonated glucosamine fragment through hydrogen bond propensity (HBP) calculations are reported. The effects of the different contents of the [Zn(Q)(MeOH)] complex on the CS biological proprieties have been evaluated, proving that the new CS@Zn films show an improved antioxidant activity, tested according to the DPPH method, with respect to pure CS, related to the concentration of the incorporated Zn(II) complex. Finally, the CS@Zn films were tried out as antimicrobial agents, showing an increase in antimicrobial activity against Gram-positive bacteria () with respect to pure CS, when detected by the agar disk-diffusion method.
通过引入过渡金属配合物作为活性成分，可以实现壳聚糖（CS）薄膜抗氧化和抗菌活性的提高。在此背景下，通过将新合成的酰基吡唑啉酮锌（II）配合物[Zn(Q)(MeOH)]嵌入到环保型生物聚合物CS基质中，制备了生物活性薄膜。在稀酸性溶液中，采用不同重量比的锌（II）配合物与CS，通过溶液浇铸法获得了均匀、无定形、柔韧且透明的CS@Zn薄膜，并采用粉末X射线衍射（PXRD）、热重分析（TGA）、差示扫描量热法（DSC）、傅里叶变换红外光谱（FT-IR）、拉曼光谱和扫描电子显微镜（SEM）技术对其进行了表征。报道了[Zn(Q)(MeOH)]的X射线单晶分析以及通过氢键倾向（HBP）计算对其与质子化葡糖胺片段的分子间相互作用的评估。评估了[Zn(Q)(MeOH)]配合物不同含量对CS生物学性能的影响，结果表明，根据DPPH法测试，与纯CS相比，新的CS@Zn薄膜具有更高的抗氧化活性，这与所掺入锌（II）配合物的浓度有关。最后，对CS@Zn薄膜作为抗菌剂进行了测试，通过琼脂圆盘扩散法检测发现，与纯CS相比，其对革兰氏阳性菌（）的抗菌活性有所提高。
